1. Field of the Invention
The invention relates to a book with a plurality of sheets each comprising two leaves which are folded in the zone of the book back.
2. Description of the Prior Art
Books are known which consist of a plurality of leaves which are sown or glued together at the book back. The term "book" as stated hereinunder shall mean a product comprising a plurality of leaves connected to each other, which also includes booklets, brochures and the like. In known books it is often the case that two leaves form a sheet which is folded in the center. Often several such sheets are stuck within each other, so that the first and the last leaf of a book belong to one sheet, the second and one but last leaf belong to the next sheet and so forth. In order to ensure the cohesion it is necessary to either glue or sow them together. This is expensive and thus limits the possible number of pages in a book. It is possible that a book is compiled from several such partial books, but this solution is also very difficult to achieve.
From the German Patent 682 075 (SCHWENKE) a book is known whose pages are provided with laps which are inserted into respective cut-outs in the cover sheet. In order to ensure coherence, the laps have to be glued.